In 1949 Sennelier started developing a range of artists quality pastels for the famous artist Pablo Picasso. Picasso was looking for a pastel with intense colour that could be applied directly and freely to a wide variety of surfaces. As a result Sennelier created an oil pastel with a soft creamy quality with all the intensity and vibrancy of conventional oil colours. However unlike oil colours Sennelier oil pastels are made using a unique combination of non aggressive oils and waxes so they can be used on almost any surface, including paper, without cracking or effecting the substrate. Oil pastels do not ever completely dry and remain heat sensitive it is therefore recommended that oil pastel works are sealed with an oil pastel fixative.